Current techniques of communicating with space satellites use radio transmitters on the ground to transmit signals to a satellite and transmitters on the satellite to send data back to the ground. Radio provides a low-power communications medium with limited bandwidth. To successfully communicate information from the satellite, the satellite must accurately aim the satellite's transmitter at a receiver, which is typically on Earth.
A laser beam may be used to send information from a laser transmitter to a laser receiver. The information is encoded onto the laser beam by the laser transmitter through modulation of the frequency of the laser beam. The information may be extracted from the laser beam and decoded by the laser receiver through detection of frequency changes in the laser beam. Laser beams provide a high-power, high-bandwidth communication medium.